So you work alone I take it? And even if you don’t, how long would it take someone to thoroughly learn the ins and outs of your framework? How much time would you need to spend teaching them?
I’m guessing it would take awhile - you admitted to not using an autoloader which means you’ve personally memorized the file paths to all you classes. It would take someone else a while to do such a memorization, so on that factoid alone I can determine your framework, however it is set up, would not be easy to learn.
These training costs are enormous and are why custom solutions like yours are losing market share. There’s a limit to the size of contract you can hope to fulfill working alone.
Running with the big dogs requires using solutions that can be rapidly deployed with the workload spread over large staffs. So enjoy your contracts valued in the thousands, your welcome to them. Meanwhile I can’t remember the last time my company took on a web application project for south of a million.